1. Field of the Invention
The present invention relates to a label affixing system for affixing a label on which predetermined content is printed, onto a conveyed object conveyed by a conveyance device.
2. Description of the Related Art
A conventional label affixing system will be described on the basis of FIG. 6.
The label affixing system is provided with a conveyance line, detectors 63, 64, a computer 65, and a label affixing machine 66.
The conveyance line is comprised of two lines, namely a first conveyance line 61 and a second conveyance line 62, such that a different type of packaging box (conveyed object) 60a, 60b can be conveyed along each line.
The detector 63 for detecting the packaging box 60a is provided to the side of the first conveyance line 61.
The detector 64 for detecting the packaging box 60b is provided to the side of the second conveyance line 62.
The detectors 63, 64 are electrically connected to the computer 65, to be described below.
The detector 63 is capable of supplying a detection signal to the computer 65 upon detection of the conveyed packaging box 60a. 
The detector 64 is capable of supplying a detection signal to the computer 65 upon detection of the conveyed packaging box* 60b. 
The computer 65 includes a control unit having various programs, a work area, and so on, a storage unit, and so on (not shown in the drawings).
The storage unit stores a plurality of printing formats, printing data such as alphabetic characters and graphics, and so on.
The printing format and printing data can be supplied to the label affixing machine 66, to be described below, as a printing pattern.
The computer 65 is electrically connected to the label affixing machine 66.
For example, when a detection signal is supplied to the computer 65 from the detector 63, the computer 65 determines that the first conveyance line 61 is operative, and can therefore call up a first printing format corresponding to the packaging box 60a and first printing data corresponding to the first printing format from the storage unit.
The first printing format and first printing data called up from the storage unit can then be transmitted to the label affixing machine 66 from the computer 65 as a first printing pattern.
Further, when a signal is supplied to the computer 65 from the detector 64, the computer 65 determines that the second conveyance line 62 is operative, and can therefore call up a second printing format corresponding to the packaging box 60b and second printing data corresponding to the second printing format from the storage unit.
The second printing format and second printing data called up from the storage unit can then be transmitted to the label affixing machine 66 from the computer 65 as a second printing pattern.
Upon reception of the first printing pattern, the label affixing device 66 can print a label L in accordance with the first printing pattern on the basis of the printing pattern transmitted from the computer 65.
The printed label can then be affixed to the packaging box 60a conveyed by the first conveyance line 61.
Upon reception of the second printing pattern, the label affixing device 66 can print the label L in accordance with the second printing pattern on the basis of the printing pattern transmitted from the computer 65.
The printed label L can then be affixed to the packaging box 60b conveyed by the second conveyance line 62.
However, the need to record a plurality of printing formats and printing data in the computer leads to an increase in the scale of the system and an increase in the amount of space that needs to be secured.
Moreover, the computer must receive a signal from one of the detectors and transmit printing information to the label affixing machine, and therefore cables connecting the computer, the detectors, and the label affixing machine to each other must be laid, leading to an increase in cable length and the generation of noise, static electricity, and so on during laying of the cable.
Japanese Unexamined Patent Application Publication H2-109893 discloses a system in which a labeling robot, a camera, a conveyor, and so on are electrically connected to a computer, and two conveyors are arranged side by side.